What are determinants in English grammar?

Answer 1

Do you mean "determiners"? Determiners are words like "the," "that," "my," "a/an," etc., that otherwise act mostly like adjectives but that don't have all the properties of normal adjectives. For instance, an adjective like "long" has comparative degree ("longer") and superlative degree ("longest"), but determiners do not (e.g. we cannot say "the-er" or "the-est" or "my-er" or "my-est").

Answer 2

Determinants are words that are placed before a noun to provide information about the quantity or identity of the noun. They can include articles (a, an, the), demonstratives (this, that), possessives (my, your), and quantifiers (some, many). Determinants help to clarify and specify the noun they are describing in a sentence.